CVE-2023-4911
A buffer overflow was discovered in the GNU C Library's dynamic loader ld.so while processing the GLIBC_TUNABLES environment variable. This issue could allow a local attacker to use maliciously crafted GLIBC_TUNABLES environment variables when launching binaries with SUID permission to execute code with elevated privileges.
ACTIVELY EXPLOITED IN THE WILD
This vulnerability is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
GNU C Library Buffer Overflow Vulnerability
GNU GNU C Library
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
11/21/2023
This vulnerability affects a common open-source component, third-party library, or a protocol used by different products. Please check with specific vendors for information on patching status. For more information, please see: https://sourceware.org/git/?p=glibc.git;a=commitdiff;h=1056e5b4c3f2d90ed2b4a55f96add28da2f4c8fa, https://access.redhat.com/security/cve/cve-2023-4911, https://www.debian.org/security/2023/dsa-5514 ; https://nvd.nist.gov/vuln/detail/CVE-2023-4911
Vulnerability Summary
CVSS v3 Score
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score (Exploitation Probability)
This vulnerability has a 64.34% probability of being exploited in the next 30 days, ranking higher than 98% of all scored CVEs.
CWE Classification
Related Vulnerabilities
Same Weakness Type(CWE-122)
ImageMagick is free and open-source software used for editing and manipulating digital images. Prior to versions 7.1.2-13 and 6.9.13-38, a heap buffer overflow vulnerability in the XBM image decoder (ReadXBMImage) allows an attacker to write controlled data past the allocated heap buffer when processing a maliciously crafted image file. Any operation that reads or identifies an image can trigger the overflow, making it exploitable via common image upload and processing pipelines. Versions 7.1.2-13 and 6.9.13-38 fix the issue.
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FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.21.0, a client-side heap buffer overflow occurs in the FreeRDP client’s `gdi_SurfaceToSurface` path due to a mismatch between destination rectangle clamping and the actual copy size. A malicious server can trigger a client‑side heap buffer overflow, causing a crash (DoS) and potential heap corruption with code‑execution risk depending on allocator behavior and surrounding heap layout. Version 3.21.0 contains a patch for the issue.
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.21.0, in ClearCodec, when `glyphData` is present, `clear_decompress` calls `freerdp_image_copy_no_overlap` without validating the destination rectangle, allowing an out-of-bounds read/write via crafted RDPGFX surface updates. A malicious server can trigger a client‑side heap buffer overflow, causing a crash (DoS) and potential heap corruption with code‑execution risk depending on allocator behavior and surrounding heap layout. Version 3.21.0 contains a patch for the issue.
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.20.1, a heap-buffer-overflow occurs in drive read when a server-controlled read length is used to read file data into an IRP output stream buffer without a hard upper bound, allowing an oversized read to overwrite heap memory. This vulnerability is fixed in 3.20.1.
Similar SeverityHIGH
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